System and method for fractional resource scheduling for video teleconferencing resources

ABSTRACT

The present invention discloses a system and method for reserving fractionally schedulable resources. The system includes a scheduling engine to receive reservation requests. The scheduling engine applies the reservation request to a resource usage table corresponding to a fractionally schedulable resource required by the reservation request. If the fractionally schedulable resource has adequate capacity to comply with the requested reservation, the scheduling engine will add the reservation request to a resource usage table.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority from U.S. Provisional PatentApplication Ser. No. 60/309,132 filed Jul. 31, 2001 and entitled,“Fractional Resource Scheduling.”

TECHNICAL FIELD

The present disclosure relates in general to the field of managing andoperating computer and communication networks and more particularly to asystem and method for fractional resource scheduling.

BACKGROUND

Network management is crucial for network systems to be properlyutilized. If network management is lacking in a particular system, theresources in that system and the network as a whole, may be eitherunderutilized or overcommitted. Underutilized network resources are awaste of scarce capital. Overcommitted network resources are more proneto failures and may lead to user dissatisfaction and frustration, makingthe network ineffective.

One way in which network resources may be managed is by providing asystem to schedule the usage of one or more network resources. However,today's scheduling systems or “scheduling engines” typically supportonly binary scheduling. That is, existing scheduling systems typicallyconsider a given resource as a whole unit that is either entirelyavailable or entirely unavailable. This type of scheduling may lead tothe underutilization of a resource because the reserved resource isoften only partially utilized by the application that is running duringthe reserved time. For example, in a video network environment amultipoint control unit (MCU) may have a bandwidth that is onlypartially utilized by a given video conference. However, after the videoconference is scheduled, the MCU will be viewed by the scheduling systemas unavailable for the reserved period, even though a portion of theMCU's bandwidth is not required by the video conference that is thereserved application.

To deal with the limitations of binary scheduling systems, one approachthat may be used is to partition a single resource into a collection ofdiscrete resources which may also be referred to as “subresources”. Eachsubresource is assigned a portion of the resource's capacity, and eachsubresource is then scheduled separately. However, this approach limitsthe flexibility of scheduling to only allow scheduling of thepredetermined portions of the resource's capacity, and it also requiresthat the user identify the proper number of subresources to match withtheir requirements.

SUMMARY

Therefore, a need has arisen for an improved scheduling system to betterutilize network resources.

A further need has arisen for a network management system that allowsfor scheduling multiple applications on a fractionally schedulableresource.

In accordance with teachings of the present disclosure, a system andmethod are described for reserving fractionally schedulable resources.The system includes a scheduling engine to receive reservation requests.The scheduling engine applies the reservation request to a resourceusage table corresponding to a fractionally schedulable resourcerequired by the reservation request. If the fractionally schedulableresource has adequate capacity to comply with the requested reservation,the scheduling engine will add the reservation request to a resourceusage table.

In one aspect, the system includes a scheduling engine able to receiveresource scheduling requests. The scheduling engine is associated withat least one fractionally schedulable resource that is able to performmultiple parallel tasks. Additionally, a plurality of other resourcesare connected to the fractionally schedulable resource. Moreparticularly, the fractionally schedulable resource may be a MultipointControl Unit in a video network with a particular maximum supportedbandwidth or a gateway component in a video network having a particularmaximum supported bandwidth, while the other resources may be videoconferencing endpoints.

In another aspect a method for scheduling fractionally schedulableresources includes receiving a resource reservation request for afractionally schedulable resource and determining the availability ofthe requested fractionally schedulable resource. If adequate capacity isavailable the fractionally schedulable resource is reserved according tothe resource reservation request. More particularly, the step ofdetermining the availability of the requested fractionally schedulableresource includes updating an associated resource usage table based uponthe resource reservation request and determining whether the resourceusage exceeds the resource's bandwidth.

The present invention includes a number of important technicaladvantages. One technical advantage is providing a scheduling engine forscheduling fractionally schedulable resources. This allows for networkresources to be more effectively utilized by employing fractionalscheduling without requiring an artificial partitioning of theresource's capacity. Another technical advantage is providing a resourceusage table. The resource usage table allows for the management andreservation of multiple applications of fractionally schedulableresources. The resource usage table also facilitates the generation ofreports, such as usage reports organized by time period. Additionaltechnical advantages of the present invention are further described inthe figures, description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present embodiments and advantagesthereof may be acquired by referring to the following description takenin conjunction with the accompanying drawings, in which like referencenumbers indicate like features, and wherein:

FIG. 1 shows a video network according to the present invention,including a scheduling engine;

FIG. 2A is a demonstrative graph showing resource usage in accordancewith the reservation system of the present invention;

FIG. 2B shows a device specific resource usage table in accordance withthe present invention;

FIG. 2C shows a device attribute table according to the presentinvention;

FIG. 3A is a reservation table according to the present invention;

FIG. 3B is a device specific resource reservation table according to thepresent invention; and

FIG. 4 shows a flow diagram of a scheduling method according to thepresent invention.

DETAILED DESCRIPTION

Preferred embodiments and their advantages are best understood byreference to FIGS. 1 through 4 wherein like numbers are used to indicatelike and corresponding parts.

Now referring to FIG. 1, a video network, depicted generally at 10, isshown. In the present embodiment video network 10 includes a firstfractionally schedulable resource (FSR) 12 connected to a second FSR 14.In the present embodiment first FSR 12 and second FSR 14 may include anynetwork resource or network component that is fractionally schedulablesuch that the resource may perform multiple parallel tasks. In anexample embodiment, FSRs 12 and 14 may have an available bandwidth suchthat a portion or fraction of that bandwidth may be utilized to performone task while the remainder of the FSRs bandwidth may be utilized toperform one or more additional tasks. In alternative embodiments, thepresent system may be implemented for scheduling any component with aresource that can be fractionally scheduled. For example, the presentsystem may be utilized for a system having a plurality of connectionswhich may be fractionally scheduled. Also, the present system may beused to fractionally schedule central processing unit (CPU) power. FSRs12 and 14 are preferably connected to plurality of network endpoints 18,20, 22, and 24, and 26, 28, and 30, respectively.

In the present embodiment first FSR 12 has a specified maximum bandwidthof 1152 kilobits per second (kbps) and second FSR 14 has a specifiedmaximum bandwidth of 768 kbps. Also in the present embodiment first FSR12 may be a multipoint control unit (MCU) which may also be referred toas a multipoint conferencing unit. The function of a multipoint controlunit is typically to connect multiple videoconferencing system endpointsinto a single conference and manage audio and video from eachparticipant end point within the conference to the others such thatgroup communication is achieved between the multiple endpoints. MCUs mayalso function to code or decode audio and video information according toknown standards, such as the H.320 and H.323 standards promulgated bythe International Telecommunication Union (ITU).

In the present embodiment second FSR 14 may be a gateway component.Often, a gateway component functions as a bridge between different typesof networks. For example, a gateway component may be used to allowH.320-type devices to communicate with H.323 type devices.

In the present embodiment video network 10 also includes first endpoint18, second endpoint 20, third endpoint 22, fourth endpoint 24, fifthendpoint 26, sixth endpoint 28 and seventh endpoint 30. Endpoints 18,20, 22, 24, 26, 28 and 30 may include endpoints within a video networksuch as videoconferencing terminals for capturing audio and videoinformation to be sent to other endpoints in the network or outside ofthe network. Each endpoint may be operable to process, code, orotherwise format the audio and/or video information according to knownstandards in order to be sent as part of a video conference. In analternative embodiment endpoints 18, 20, 22, 24, 26, 28 and 30 maycomprise any suitable network component connected either directly orindirectly to a fractionally schedulable resource. It should be notedthat the number and arrangement of endpoint devices included in videonetwork 10 is intended for demonstrative purposes, and in an alternativeembodiment the number and arrangement of endpoints can varysignificantly.

Each endpoint also has a specified bandwidth. For instance, in thepresent embodiment, first endpoint 18 has a specified maximum bandwidthof 128 kbps, second endpoint 20 has a specified maximum bandwidth of 384kbps, third endpoint 22 has a maximum bandwidth of 128 kbps, fourthendpoint 24 has a maximum bandwidth of 384 kbps, fifth endpoint 26 has amaximum bandwidth of 384 kbps, sixth endpoint 28 has a maximum bandwidthof 256 kbps and seventh endpoint 30 has a maximum bandwidth of 128 kbps.Endpoints 18, 20, 22 and 24 are operatively connected to first FSR 12such that first FSR 12 may selectively connect two or more endpoints 18,20, 22 and 24. Endpoints 26, 28 and 30 are operatively connected tosecond FSR 14 such that second FSR 14 may connect these endpoints to thefirst FSR 12 and the endpoints connected thereto.

First FSR 12 is preferably connected to call set up module 46. In analternate embodiment, multiple devices including any or all of thedevices shown in FIG. 1 may be operably connected to call setup module46. Call setup module 46 is operably connected with scheduling engine16. Call setup module 46 functions to establish video conferences andmay communicate with scheduling engine 16 to determine which telephoneconferences have been scheduled. In the present embodiment, call setupmodule 46 uses scheduling engine 16 primarily as an advisory tool todetermine which video conferences need to be established, at what times,and with which devices. However, in an alternative embodiment, callsetup module 46 may incorporate policies requiring calls be scheduledthrough scheduling engine 16.

Resource reservation requests may be received from any suitablerequester. In the present embodiment, resource reservation requests maybe received via a reservation request application 48 connected toCommunication network 49. Communication network 49 may be any suitablenetwork for communicating with a plurality of users such as an IPnetwork. In the present embodiment, network 49 is an IP network such asthe Internet and is further accessible to user stations 47. A user mayoperate a user station 47, such as a PC, server or work stationconnected to network 49, to access resource reservation application 48via Internet 49, to submit a resource reservation request. Additionally,a system administrator or system manager may submit a resourcereservation request directly (not expressly shown) to scheduling engine16. Accordingly, users may to submit a reservation request eitherdirectly via reservation request application 48 or indirectly bycontacting a network administrator.

Scheduling engine 16 preferably includes reservation table 40, deviceattribute table 41, first resource usage table 42 and second resourceusage table 44. In a preferred embodiment scheduling engine 16 receivesincoming resource reservation requests, such as video conferencereservation or scheduling requests, from reservation request application48 or directly from a system administrator. In the present embodimentresource usage tables, 42 and 44, are included which correspond withfirst FSR 12 and second FSR 14 as shown in FIG. 1. Resource reservationtable 40 (as shown in FIGS. 3A and 3B) is maintained by schedulingengine 16 and may include both a record of all resources used by aparticular reservation, and may also include device specific reservationtables (as shown in FIG. 3B) that include only resource reservations fora particular device. Scheduling engine 16 also maintains deviceattribute table 41, also shown in FIG. 2C, to maintain a listing ofselected device attributes, capabilities, and features. For example,device attribute table 41 may maintain a record of the maximum bandwidthof each fractionally schedulable resource.

In an alternative embodiment, resource usage tables 42 and 44, as wellas reservation table 40 and device attribute table 41 may be maintainedseparately from scheduling engine 16, such as on an associated server.In another alternative embodiment, a resource usage table may beincluded for each of a plurality of FSRs associated with schedulingengine 16. In still yet another alternative embodiment, a globalresource usage table may be included which combines the resource usagedata for multiple FSRs in a single table.

After scheduling engine 16 receives an incoming resource reservationrequest, scheduling engine 16 preferably determines which resources areinvolved with the particular request. This step may include determiningthe end points involved in a given reservation request and identifyingthe FSRs required to comply with the reservation request. In analternative embodiment, the required endpoints and/or FSRs may bespecifically requested in the resource reservation request or may bedetermined by a system administrator.

Scheduling engine 16 then queries the corresponding resource usagetables. For instance, if both first FSR 12 and second FSR 14 arerequired to comply with a particular reservation request, theoverlapping resource usage records are obtained from both resource usagetables 42 and 44. Scheduling engine 16 then examines each overlappingusage record to determine whether adding the requested usage to eachrecord would exceed the capacity of the desired resource. If schedulingengine 16 determines that a reservation causes resource usage to exceedcapacity, scheduling engine 16 then acts to reject the resourcereservation request. In a preferred embodiment, scheduling engine 16 maycommunicate a notification to the requester and/or the systemadministrator that the reservation request has been denied. However ifthe resource usage does not exceed the capacity of the resource,scheduling engine 16 then includes the resource reservation request intoreservation table 40, updates the resource usage tables 42 and 44, andmay preferably send a confirmation of the reservation to the requestor.

In the present embodiment, the steps involved with updating a resourceusage table may vary according to the make up of the existing resourceusage table and characteristics of the resource usage request. For agiven usage record U (having an associated resource usage value and aspecified start time and end time) and a resource usage request C (witha specified resource usage requirement and a start time and end time)where U and C overlap in time, if the period of U falls completelyinside the period of C, the resource usage value of U is increased bythe resource usage required for C. For instance, in the presentembodiment the resource usage requirement is bandwidth required duringthe period of interest.

In the event that the period of U begins before the start of C and endsbefore the end of C but after the start time of C, U is updated tochange the end time of U to the start time of C. A new usage record, U1,is then added with a start time equal to the start time of C and an endtime equal to U's original end time. The usage value of U1 is then setequal to U's original usage value plus the usage required for C. In analternative embodiment, U may be updated to change the start time of Uto equal the start time of C and increase the usage value to equal U'soriginal usage value plus the usage required for C. Also, a new recordU1 may be created with a start time equal to the original start time ofU, an end time equal to the start time of C, and a usage value equal tothe original usage value of U. Other equivalent steps for updating andcreating usage records may be embodied in further alternativeembodiments.

In the event that U begins after the start time of C and before the endtime of C, and ends after the end time of C, a new usage record U1 isadded. The new usage record U1 has a start time equal to the originalstart time of U and has an end time equal to the end time of C. Theresource usage value for U1 is set to be the original usage of U plusthe required usage of C. Lastly the start time of U is adjusted to beequal to the end time of C and otherwise retains its original end timeand resource usage requirement. In an alternative embodiment, U may beupdated to have an end time equal to the end time of C and a usage valueequal to the original usage value of U plus the usage value of C; a newusage record U1 is also created having a start time equal to the endtime of C and an end time equal to the original end time of U. The usagevalue assigned to U1 is equal to the original usage value of U.

In the event that U begins before the start time of C and ends after theend time of C, several actions take place. First, U is updated to changeits ending time to the start time of C. A new record, U1 is added withstart and end times matching C and a usage value equal to the usagevalue of U plus the usage value of C. Finally, another record U2 isadded with a start time equal to the end time of C and an end time equalto the original end time of U. The usage value of U2 is set to equal theusage value of U. As one of ordinary skill in the art would note, inthis case the original usage record U is updated to become the first ofa series of three usage records that cover the original time period ofU. Such a person would also note that the original record could beupdated to become the second or the third usage record of the serieswithout departing from the scope of the present invention.

Finally, if there is any time interval between the start and end timesof C for which there is no corresponding usage record, then for eachsuch time interval a new usage record U is created. The start and endtimes of U are set to match the start and end times of the uncoveredinterval, and the usage of U is set equal to the usage value of C.

Alternatively, scheduling engine 16 may receive a request to cancel anexisting reservation, such as reservation 1, stored in reservation table40 (as shown in FIG. 3A, below). The cancellation of an existingreservation may be accomplished through either accessing reservationrequest application 48 and submitting a reservation cancellation requestor by contacting a system administrator. In this example, thereservation table is preferably examined to determine which resourcesare required to participate in a reservation, as well as the usagerequired for each resource in the reservation. For each device found inthe reservation table, for the reservation to be cancelled, theoverlapping resource usage records from 42 and/or 44 are obtained. Eachof these records is then updated by subtracting the usage of thatresource in that reservation from the usage recorded in the reservationrecord, and then the record from reservation table 40 corresponding tothis device is preferably deleted. In an alternative embodiment, anyrecord whose usage value would normally be updated to a zero value wouldinstead be deleted from the resource usage table. Allowing forreservations to be canceled facilitates keeping the reservation systemup to date, thereby allowing the reservation and usage tables toaccurately reflect the availability of the FSRs.

Now referring to FIG. 2A, a graphic representation of a resource usagetable depicted generally at 50 is shown. Resource usage graph 50includes bandwidth 54 shown along the vertical axis and time 52 shownalong the horizontal axis. In one embodiment, time 52 may be regularlyupdated such that time entries from a past period and a lengthier futureperiod, are automatically added in order to facilitate resourcereservation requests in the future. For example, time 52 may beregularly updated to contain resource usage data for a time periodspanning from a week prior to the present to a year from the presentdate. Resource usage graph 50 further includes a maximum bandwidth 56corresponding to the maximum bandwidth of the corresponding FSR asstored in device attribute table 41. In the present embodiment, resourceusage graph 50 is demarcated into a series of time intervalscorresponding to the different time intervals where resource usagechanges. Accordingly, as the usage table (as shown in FIG. 2B, below) isupdated, the time intervals corresponding to the time intervals ofresource usage are also updated.

Now referring to FIG. 2B, a device specific resource usage table 70 isshown. Resource usage table 70 includes, for a particular FSR, thecumulative scheduled resource usage 78 during periods 72. Periods 72 aredelineated with appropriate start 74 and end 76 times. Scheduling engine16 updates start 74 and end 76 times appropriately after a reservationthat makes use of FSR1 12 has been added to or removed from reservationtable 40 or when processing a reservation request that refers to FSR1 12to determine whether a request should be granted.

Scheduling engine 16 may selectively obtain records from resource usagetable 42 in order to determine whether a particular resource (in thiscase, FSR1) will exceed capacity after a resource reservation request isgranted. Scheduling engine 16 may also insert, add, or update recordsinto resource usage table 42 in response to a resource reservationrequest. In one embodiment, scheduling engine 16 may also selectivelyupdate and/or delete selected records of resource usage table 42 inresponse to a resource reservation cancellation or a received end ofsession notification for a reservation that makes use of FSR1 12. An endof session notification may be sent to scheduling engine in the eventthat a reserved resource session, such as a video conference, has endedearly. This allows the resource usage table to maintain accuracy,thereby maximizing network resources.

Now referring to FIG. 2C, a device attribute table 80 is shown. Deviceattribute table 80 preferably maintains a listing of FSRs associatedwith scheduling engine 16 and selected device attributes. In the presentembodiment, device attribute table 80 includes a listing of associatedFSRs 82 and the maximum bandwidth 84 of each FSR. In an alternativeembodiment, device attribute table may include additional or alternativefractionally schedulable attributes of associated devices as well asadditional general attributes of the associated devices. Deviceattribute table 80 may be periodically updated by a systemadministrator.

Now referring to FIG. 3A a reservation table depicted generally at 40 isshown. The reservation table includes resource reservation informationincluding reservation number 86, requester information 88, start time89, end time 90, bandwidth requirement 91, and resource 92. Start time89 preferably includes the day and time at which a particular resourcereservation begins. End time 90 preferably includes an ending orstopping day and time for a particular resource reservation. In thepresent embodiment, resource 92 includes only one FSR affected by aparticular resource reservation. For resource reservations which requiremultiple FSRs, reservation table 40 maintains a separate record for eachFSR. For example, reservation number 1 requires both FSR1 and FSR2 whichare separately listed in reservation table 40. Maintaining separaterecords allows the system to more easily cope with resource reservationsin which different FSRs have different bandwidth requirements. In analternative embodiment, reservations requiring multiple FSRs may becondensed into a single record. In another embodiment, bandwidth usagefor particular FSRs may be kept in a table separate from the reservationtable, but then joined to the data in the reservation table at run time.In another embodiment, additional resource attributes may be listed fora reservation. In yet another embodiment, the reserved attribute (suchas band width) and the amount of that attribute required are each listedin a separate column of reservation table 40.

Now referring to FIG. 3B, a device specific resource reservation table94 is shown. Device specific reservation table includes reservationnumber 86, start 89 and end 90 times, resource 92, and bandwidthrequirement 91. Device specific reservation table 94 is preferablygenerated from the information contained in reservation table 40 for asingle FSR, in this case, FSR1. The device specific reservationinformation may then by used to generate device specific resource usagetable 42. In an alternative embodiment, the step of creating a devicespecific reservation table may be skipped by obtaining reservationinformation for a specified device from reservation table 40 andgenerating resource usage table 42 without the use of device specificreservation table 94. Similar to FIG. 3A, in an alternative embodimentdevice specific reservation table 94 may include alternate or additionaldevice attributes for reservation. In another embodiment device specificreservation table 94 may display the reserved attribute (such as bandwidth) and the amount of that attribute required in separate columns.For instance, for a particular reservation the type of attribute beingreserved is listed in a column and the value of the resource beingrequested is listed in an adjacent column.

Now referring to FIG. 4, a flow diagram of a resource scheduling methodis depicted at 100. Resource scheduling method 100 begins at 102. Firsta method includes receiving a resource reservation request 104. Thisstep may preferably include receiving a resource reservation requestfrom a reservation request application (as shown in FIG. 1) such as aweb page or similar interface that allows a user to submit a requestthrough a network. This step may also include receiving a reservationrequest directly from a network administrator. Next, the method involvesdetermining which FSRs are required to meet the requirements of thereceived resource reservation request 106. This step may includeutilizing a network utility to determine which FSRs are required toimply with a reservation request. Alternatively, the required FSRs maybe identified by a network administrator familiar with the network.Also, the reservation request web page may also allow a user to indicatethe required FSRs for a particular reservation request.

Following this step the received resource reservation request isanalyzed with respect to the resource usage table corresponding to theeffected resources 108. In the event that multiple resources arerequired to comply with a request, the reservation request maypreferably be analyzed with respect to each respective resource usagetable. After calculating the effect of the reservation on theappropriate resource usage table or tables, the scheduling enginedetermines whether any of the effected FSRs will exceed capacity 110,with the addition of the new resource reservation. If any FSR willexceed capacity, the resource reservation request is rejected 115 andthe system awaits the receipt of a new resource reservation request 102.Additionally, the system may send a notice to the requestor that thereservation request has been rejected. Such a notification may be sentby email or another suitable method.

However, if the resource usage does not exceed capacity, the resourcetables are then updated for all the required resources associated withthe request 111. The reservation is then added to the appropriateresource reservation tables 112. The request may then be formallygranted 113 by sending an appropriate notification to the requester.

In an alternative embodiment, resource usage table 42 may beperiodically queried (not expressly shown) by a call set-up component(as shown in FIG. 1) to aid in the placement of calls in a videonetwork.

In operation, scheduling engine 16, having previously scheduledresources according to reservation table 40, may receive a resourcereservation request for first FSR 12, for a period between 14:30 and15:15 on 10.1.01, requiring a bandwidth of 384 kbps. Scheduling engine16 then preferably applies the reservation to the resource usage table42. During the period between 15:00 and 15:15, the request resource willexceed its maximum capacity. The request is therefore rejected andresource usage table 42 is restored to its original state.

Next, scheduling engine 16, may receive a resource reservation requestfor first FSR 12, for a period between 13:15 and 14:30 on 10.1.01,requiring a bandwidth of 384 kbps. Scheduling engine 16 then preferablyapplies the reservation to the resource usage table 42. The applicationof the resource reservation request indicates that the requestedresource will not exceed its maximum capacity. The request is thereforeaccepted and resource usage table 42 is updated to reflect the additionof this resource reservation request. Reservation table 40 is thenupdated to reflect the accepted reservation and the reservation requestmay then be granted.

Although the disclosed embodiments have been described in detail, itshould be understood that various changes, substitutions and alterationscan be made to the embodiments without departing from their spirit andscope.

1. A system for scheduling networked video teleconferencing resources,comprising: at least one fractionally schedulable video teleconferencingresource having a maximum bandwidth and configured to simultaneouslyconduct a first video teleconference between first and second endpoints,via a first portion of said maximum bandwidth, and a second videoteleconference between third and fourth endpoints, via a second portionof said maximum bandwidth; and a video teleconferencing schedulingengine configured to receive at different times a first and second videoteleconferencing resource scheduling request corresponding to thesimultaneous first and second video teleconferences, and to maintain avideo teleconferencing resource usage table including a usage recordidentifying, by task and by requestor, one of a portion of the maximumbandwidth in use during a first predetermined window of time and aportion of the maximum bandwidth reserved for future use in a secondpredetermined window of time equal in length to the first predeterminedwindow of time, wherein each usage record includes a corresponding taskstart time, task end time, total amount of reserved bandwidth, and areserved resource identifier; each video teleconferencing resourcescheduling request includes a corresponding requested task start time,task end time, total amount of requested bandwidth, and a requestedresource identifier; and the video teleconferencing scheduling engine isconfigured to compare each video teleconferencing resource schedulingrequest in order of time of receipt to a stored usage record, and toindividually grant each video teleconferencing resource schedulingrequest only if a grant will not result in an assignment within one ofsaid first and second predetermined periods of time of a total bandwidthof the fractionally schedulable video teleconferencing resource greaterthan the maximum bandwidth of the fractionally schedulable videoteleconferencing resource.
 2. The system of claim 1, wherein thefractionally schedulable video teleconferencing resource is configuredto connect with a plurality of video teleconferencing endpointresources.
 3. The system of claim 2 wherein the fractionally schedulablevideo teleconferencing resource further comprises a Multipoint ControlUnit having a maximum bandwidth.
 4. The system of claim 2 wherein thefractionally schedulable video teleconferencing resource furthercomprises a video teleconferencing gateway having a maximum bandwidth.5. The system of claim 2 wherein the fractionally schedulable videoteleconferencing resource further comprises a system having a pluralityof video teleconferencing connections.
 6. The system of claim 2 whereinthe fractionally schedulable video teleconferencing resource furthercomprises a processor having a maximum processing power.
 7. The systemof claim 2 wherein the plurality of video teleconferencing endpointresources comprise endpoint resources within a video teleconferencingnetwork.
 8. The system of claim 2 wherein the fractionally schedulablevideo teleconferencing resource further comprises a ITU standard H.320compliant video teleconferencing resource having a bandwidth.
 9. Thesystem of claim 2 wherein the video teleconferencing scheduling engineis configured to determine the resource usage of a fractionallyschedulable video teleconferencing resource for a requested period. 10.The system of claim 2 wherein the video teleconferencing schedulingengine is configured to receive video teleconferencing resourcescheduling requests from a network administrator.
 11. The system ofclaim 2 further comprising the video teleconferencing scheduling engineto receive video teleconferencing resource scheduling requests from avideo teleconferencing reservation request application.
 12. The systemof claim 2 further comprising a video teleconferencing reservationrequest application coupled to the video teleconferencing schedulingengine for submitting video teleconferencing resource schedulingrequests and accessible to a communications network.
 13. A device forscheduling at least one fractionally schedulable video teleconferencingresource having a maximum bandwidth and configured to simultaneouslyconduct a first video teleconference between first and second endpointsvia a first portion of said maximum bandwidth and a second videoteleconference between third and fourth endpoints via a second portionof said maximum bandwidth, comprising: a video teleconferencingscheduling engine configured to receive at different times a first andsecond video teleconferencing resource scheduling request correspondingto the simultaneous first and second video teleconferences, and tomaintain a video teleconferencing resource usage table including a usagerecord identifying, by task and by requestor, one of a portion of themaximum bandwidth in use during a first predetermined window of time anda portion of the maximum bandwidth reserved for future use in a secondpredetermined window of time equal in length to the first predeterminedwindow of time, wherein each usage record includes a corresponding taskstart time, task end time, total amount of reserved bandwidth, and areserved resource identifier; each video teleconferencing resourcescheduling request includes a corresponding requested task start time,task end time, total amount of requested bandwidth, and a requestedresource identifier; and the video teleconferencing scheduling engine isconfigured to compare each video teleconferencing resource schedulingrequest in order of time of receipt to a stored usage record, and toindividually grant each video teleconferencing resource schedulingrequest only if a grant will not result in an assignment within one ofsaid first and second predetermined periods of time of a total bandwidthof the fractionally schedulable video teleconferencing resource greaterthan the maximum bandwidth of the fractionally schedulable videoteleconferencing resource.
 14. A method for scheduling at least onefractionally schedulable video teleconferencing resource having amaximum bandwidth and configured to simultaneously conduct a first videoteleconference between first and second endpoints via a first portion ofsaid maximum bandwidth and a second video teleconference between thirdand fourth endpoints via a second portion of said maximum bandwidth,comprising: receiving at different times a first and second videoteleconferencing resource scheduling request corresponding to thesimultaneous first and second video teleconferences; maintaining a videoteleconferencing resource usage table including a usage recordidentifying, by task and by requestor, one of a portion of the maximumbandwidth in use during a first predetermined window of time and aportion of the maximum bandwidth reserved for future use in a secondpredetermined window of time equal in length to the first predeterminedwindow of time, wherein each usage record includes a corresponding taskstart time, task end time, total amount of reserved bandwidth, and areserved resource identifier, and each video teleconferencing resourcescheduling request includes a corresponding requested task start time,task end time, total amount of requested bandwidth, and a requestedresource identifier; comparing each video teleconferencing resourcescheduling request in order of time of receipt to a stored usage record;and individually granting each video teleconferencing resourcescheduling request only if a grant will not result in an assignmentwithin one of said first and second predetermined periods of time of atotal bandwidth of the fractionally schedulable video teleconferencingresource greater than the maximum bandwidth of the fractionallyschedulable video teleconferencing resource.